<% monitoring = Commentableship.find(:first, :conditions => ["user_id = ? and commentable_id = ? and commentable_type = ? and is_watching = 1", current_user.id, model.id, type]) %>
<input id="monitor_checkbox" type="checkbox" <%= "checked='checked'" if !monitoring.nil? %> 
  onclick="if (this.checked) {<%= remote_function :url => commentableships_path(:commentable_type => type, :commentable_id => model.id, :is_watching => true, :escape => false), :method => :post %>} else {<%= remote_function :url => commentableships_path(:commentable_type => type, :commentable_id => model.id, :is_watching => false, :escape => false), :method => :post %>}" />
<label id="monitor_label" for="monitor_checkbox">Следить за комментариями</label>